Helicopter sling-line grapple hook



FIG. 1 is a perspective view of the helicopter sling-line grapple hook showing my new design;

FIG. 2 is a front view thereof;

FIG. 3 is a side perspective view thereof;

FIG. 4 is a top view thereof;

FIG. 5 is an exploded view thereof; and,

FIG. 6 is another perspective view thereof.

The bottom view of the helicopter sling-line grapple hook is not part of the claimed design. 

The ornamental design for a helicopter sling-line grapple hook, as shown. 